explosive sheep works with board wipes to increase the damage by 2 and/or clean up things that would be left behind due to deathrattles (possessed villager, infested wolf) or divine shields (c'thun's chosen)
in certain situations it can be used by itself as a way of slowing your opponent's board development, but this will usually only occur versus heavily aggressive decks

wild pyromancer --> shadow word: pain

if you find yourself going up against a lot decks that run a few things with 3 attack and 5 or 6 health that are hard to get rid of you could consider this
keep in mind that unless these creatures are being played on an open board you might be better off with a board wipe + explosive sheep

both of these swaps are more situational than pyromancer, so think carefully about the meta you're in before making them

Also, I do not recommend swapping out loot hoarder or gnomish inventor because this deck has very very few ways to proactively get onto the board, and both of these cards are ways of doing so while also cycling through your deck to complete the combo. These cards will rarely make advantageous trades with your opponent's creatures, which is why most decks do not run them, but they can absorb damage so that you can stall for a better value board wipe, or they can whittle down a big creature to be within wipe range, all without losing card advantage.

why did lightning bolt get removed? it was 2 mana for 3 damage and synnergizes with tunnel trogg and sentinel
why is stormforged axe not run? it's 3 mana for 6 damage and synnergizes with tunnel trogg and sentinel
why did master of evolution get included? it's a very mid-range play that needs a damaged creature or 0/2 totem target in order to reach full potential. Many games it sits in my hand as a dead card until I run out of other options because it's just too slow and situational.

Given that this list was made by a pro I'm sure that all the decisions are correct.
However, I don't understand why you would drop the frothing berserkers for fierce monkeys.
Could you explain that to me?

This deck is really fun
except that most classes have at least one (if not more) way of board wiping and killing all your patrons
and everybody knows to save it for when you combo off and fill your board with patrons
and then you get 3 for 1'ed
and then you lose
and then you cri evry tim

This deck is really good for climbing the lower ranks.
It's really fun to play, and really cheap to make compared to most decks (assuming you've played the campaigns).
My only problem with it is that it has pretty close to a 0% winrate versus control warrior and has a very hard time beating handlock unless your opponent has never seen the deck before and lets themself get within savage roar range without taunts on the field.
Once you get up to about rank 13 or rank 12, the current meta is almost all control warrior and handlock, which makes advancing past these ranks near impossible until the meta shifts.

Still, if you're looking for a cheap, fast, fun climb through the low/mid ranks this is a great option.